It is time for midwives to perform intrapartum ultrasonography for fetal head station, position and cervical dilation

Abstract

Objective: Digital vaginal examination (DVE) is a commonly used method in delivery wards to monitor the progress of labor, but it is considered uncomfortable by pregnant women and can lead to infectious complications, such as chorioamnionitis. At the same time, the performance of intrapartum ultrasonography (IPU) is increasing. IPU has a higher inter-observer and intra-observer agreement than DVE. In this study, we evaluated the agreement between IPU and DVE measurements performed by midwives trained in ultrasonography and a specialist obstetrician. Using these data, we assessed the feasibility of midwives administering IPU in delivery rooms for fetal head station and position and cervical dilation.

Methods: This prospective study was conducted on the delivery ward at a tertiary healthcare hospital between 1 March and 1 May 2021. The study included women with low-risk pregnancies with a singleton vertex presentation who were admitted to the delivery ward after 37 weeks of gestation. The two midwives underwent a theoretical and practical training program on patients led by an expert obstetric consultant. Cervical dilation, fetal head station and position were recorded through IPU and DVE measurements conducted by two midwives and one expert obstetrician. Cohen's kappa with squared weights was used to assess the agreement between observers. The discomfort score during the examinations was also obtained from the pregnant women and recorded (0 = no discomfort, 10 = very uncomfortable).

Results: The study included 196 pregnant women. There was mostly moderate or substantial agreement between the midwives and obstetric consultant in the variables of cervical dilation, fetal head level and position determined by DVE. In all IPU measurements, these agreements were perfect among all observers. While the intra-observer agreement of the obstetric consultant in IPU and DVE was perfect, in midwives, it was analyzed as substantial in cervical dilation, fair and moderate in the head station, and moderate and perfect in head position. The mean discomfort scores of the pregnant women due to IPU and DVE were 2.89 ± 1.49 and 5.98 ± 2.02, respectively. The differences in discomfort scores between the two examinations were detected to be statistically significant (p < 0.001).

Conclusion: IPU can be used by midwives in delivery wards to accurately determine the fetal head position and station and cervical dilation without causing discomfort to pregnant women.

Keywords: Cervical dilatation; fetal head position; fetal head station; sonographic assessment; ıntrapartum ultrasonography.